Definitions
The following terms as used in this specification and the appended claims shall have meanings as follows:
"Line-of-sight" (sometimes abbreviated "LOS axis") is intended to have generic meaning covering both: (A) the axis of an energy beam, and (B) an optical line-of-sight axis through an optical train.
"Virtual axis (or axes) of deflection of an LOS axis", or simply "Virtual axis of deflection" has reference to one or both, as the case may be, of two mutually orthogonal virtual axes which are effectively present in conjunction with the disclosed series of pivotal mirrors. These virtual axes are present as the result of the combined effects of operation of all the individual mirrors of the series of pivotal mirrors, as will become apparent as the description proceeds. Since the locations of these axes do not coincide with any structure which appears in the drawing, the modifier word "virtual" has been used as the name given to them.
"Pivotal deflection about a linear pivot axis" or simply "pivotal deflection" has reference to the individual operation of the series of pivotal mirrors of the apparatus disclosed and claimed herein. Unless otherwise qualified, it is intended to have generic meaning covering both the cases of: (A) deflection of a mirror about a linear pivot axis which passes through the center of the mirror, and (B) deflection of a mirror about a pivot axis which is displaced by a distance of separation from the center of the mirror.